The Australian fruit fly parasitoid Diachasmimorpha kraussii (Fullaway): Life history, ovipositional patterns, distribution and hosts (Hymenoptera : Braconidae : Opiinae)
Diachasmimorpha kraussii is a larval-pupal parasitoid of tephritid fruit flies in Australia. It is currently being considered for release against fruit fly pests in Hawaii. Virgin D. kraussii females lived longer (mean = 31.4 days; n = 10) than mated females (mean = 27.6 days; n = 10) by a factor of about 12%. The rate of offspring production per day by virgins (about four emerging adults per day) was the same as that of mated females, so virgins tended to produce more offspring in total (mean = 125) than did mated females (mean = 112), but the difference was not statistically significant. The time between egg deposition and emergence of the resultant adult varied from 16 days to more than 300 days, and males achieved maximum emergence before females. Adult wasps emerged at any time of the photophase, both under laboratory and field conditions, but the rate declined towards the end of the daylight period. Adult females oviposited more actively during the day than at night (30.8 vs 19 adults), and the pattern tended to be stronger when wasps were exposed to hosts initially during the scotophase (37.4 vs 18.4 adults). Mated females produced female-biased brood sex ratios of about 0.28 (proportion of males) on average, and the older the mother wasps the greater the proportion of female offspring produced. Diachasmimorpha kraussii is distributed only in northern and eastern Australia, as far south as New South Wales. It has been recorded from 13 host fly species and in association with 18 host plant species